1940 UA valve covers and tappet guides

[EricOlson]

Hello all, in addition to the cam I have listed in the "wanted" section for my 1940 UA, I am also going to be replacing my valve covers and tappet guides. I am looking at installing the 37-39 threaded style valve spring covers sold by Replicant Metals. https://www.replicantmetals.com/products-bigtwin.html. In order to do this I will also have to switch my tappet guides to threaded style. It looks like the WL and U models are interchangeable with each other, but possibly with the VL also? Is this correct, and if so has anyone had success with sourcing some good ones? Either repop or NOS is fine with me, as long as they will install correctly and hold up over time. The bike won't be getting judged, so I'm not worried about being correct for the year, I just want it to work.

[kitabel]

Yes, same as 45 & VL, no experience with those covers.

[chuckthebeatertruck]

Those replicant covers look identical to the colony kit. I used one of the colony kits a few years ago on a 46ul. The threads were rough. I eventually covered them in lapping paste and worked them back and forth. Otherwise, it took excessive force to fully screw the down. It sounds worse than it was. With that done, they sealed a treat. BUT, you do need to buy the service wrenches. It really makes life easy.

I bought all my tappet guides at swaps so I could choose the best ones.

[larry]

Colony had a problem with plating being too heavy on threaded parts. The problem may have been solved. Call and ask.

[kitabel]

The problem is not technical, it's that the people doing the masking don't know what the parts are, or what they do.

[vph-d]

You shouldn't have too much of a problem finding used WL tappet guides
VPH-D

[EricOlson]

Thanks all. Asking around with some of my local friends confirmed the same thing about the threads being rough due to plating. The Replicant Metal ones are cad plated, so it would be thin and shouldn't interfere with tightening them. And I will get wrench, sounds like it will make life easier, and I'm always in favor of that!

[larry]

It's the cad plating that was the problem.

[EricOlson]

It's the cad plating that was the problem.

I had heard it was the chrome plating that was the issue. I'll report back how these ones go on and if I have to chase the threads like chuckthebeatertruck did.

[T. Cotten]

I had heard it was the chrome plating that was the issue. I'll report back how these ones go on and if I have to chase the threads like chuckthebeatertruck did.

If its a real problem, Eric..

I would mask off the pretty part (electrician's tape works best),

Then blast the threads with ALOX.

And finish with a fine wire or ADALOX wheel.

....Cotten

[41craig]

Why do you want to replace the tappet guides and valve covers ??

Craig

[EricOlson]

Why do you want to replace the tappet guides and valve covers ??

Craig

I want to go to the threaded style because the spring style seem to leak on me a fair amount. I hope to see less leakage on the threaded ones.

[Steve Slocombe]

I'm struggling with the later UL valve covers, all repro and with a repro spring tool. Any tips out there?

[Steve Slocombe]

The UL used the VL tappet guides in 1937 and 1938. The valve covers are as the VL, but with the top one 1/4" taller to compensate for the longer stroke motor. I think Colony are also reproducing these. It's handy to have both VL valve cover tools, the hook at the bottom as well as the slimline wrench for the middle section. Sealing depends on the rubbers. My last Colony set came with O-rings that didn't do the job. I now use the 45 ones with no problems. Originally the seals were leather strips with angled ends, so you could replace the seals without pulling the cylinder. Haven't seen these for a long time, and guessing they were fixed with 'the old reliable shellac' as the accessory catalogs.

The screw style tappet guides and lifters last a long time and used ones are usually OK for further service, especially if you have several and can mix and match. Most will need new rollers. New guides and new lifters are available, and in oversizes too.

[larry]

If assembly is a problem, filing a lead on the retainer tab helps tremendously. valve cover retainer.JPG